diff --git a/src/slic3r/GUI/Field.hpp b/src/slic3r/GUI/Field.hpp
index 3273f84c9..8391a111b 100644
--- a/src/slic3r/GUI/Field.hpp
+++ b/src/slic3r/GUI/Field.hpp
@@ -115,7 +115,7 @@ public:
     /// subclasses should overload with a specific version
     /// Postcondition: Method does not fire the on_change event.
     virtual void		set_value(const boost::any& value, bool change_event) = 0;
-    
+
     /// Gets a boost::any representing this control.
     /// subclasses should overload with a specific version
     virtual boost::any&	get_value() = 0;
@@ -128,6 +128,8 @@ public:
 
 	virtual wxString	get_tooltip_text(const wxString& default_string);
 
+    void				field_changed() { on_change_field(); }
+
     // set icon to "UndoToSystemValue" button according to an inheritance of preset
 //	void				set_nonsys_btn_icon(const wxBitmap& icon);
 
diff --git a/src/slic3r/GUI/Tab.cpp b/src/slic3r/GUI/Tab.cpp
index 79952f184..c37e04ab9 100644
--- a/src/slic3r/GUI/Tab.cpp
+++ b/src/slic3r/GUI/Tab.cpp
@@ -1587,11 +1587,11 @@ void TabPrinter::build_printhost(ConfigOptionsGroup *optgroup)
 		auto sizer = new wxBoxSizer(wxHORIZONTAL);
 		sizer->Add(btn);
 
-		btn->Bind(wxEVT_BUTTON, [this, parent, optgroup](wxCommandEvent e) {
+		btn->Bind(wxEVT_BUTTON, [this, parent, optgroup](wxCommandEvent &e) {
 			BonjourDialog dialog(parent);
 			if (dialog.show_and_lookup()) {
 				optgroup->set_value("print_host", std::move(dialog.get_selected()), true);
-				// FIXME: emit killfocus on the edit widget
+				optgroup->get_field("print_host")->field_changed();
 			}
 		});
 
@@ -1605,7 +1605,7 @@ void TabPrinter::build_printhost(ConfigOptionsGroup *optgroup)
 		auto sizer = new wxBoxSizer(wxHORIZONTAL);
 		sizer->Add(btn);
 
-		btn->Bind(wxEVT_BUTTON, [this](wxCommandEvent e) {
+		btn->Bind(wxEVT_BUTTON, [this](wxCommandEvent &e) {
 			std::unique_ptr<PrintHost> host(PrintHost::get_print_host(m_config));
 			if (! host) {
 				const auto text = wxString::Format("%s",
@@ -1646,6 +1646,7 @@ void TabPrinter::build_printhost(ConfigOptionsGroup *optgroup)
 				wxFileDialog openFileDialog(this, _(L("Open CA certificate file")), "", "", filemasks, wxFD_OPEN | wxFD_FILE_MUST_EXIST);
 				if (openFileDialog.ShowModal() != wxID_CANCEL) {
 					optgroup->set_value("printhost_cafile", std::move(openFileDialog.GetPath()), true);
+					optgroup->get_field("printhost_cafile")->field_changed();
 				}
 			});